Which newcomer will make the biggest impact in the AFC South this season? Our roundtable reporters give their picks.

Sarah Barshop, Houston Texans reporter: Texans safety Tyrann Mathieu. When the Texans heard the Arizona Cardinals were cutting Mathieu, they quickly jumped at the opportunity to sign a former All-Pro safety coming off the healthiest of his first five NFL seasons. The Texans will start Mathieu at safety and allow him to focus on the position -- something he's said he didn't really have the chance to do in Arizona -- but will certainly use his versatility and ability to find the ball to their advantage. Mathieu boosts a secondary that dropped from the No. 2 defense in passing yards allowed per game in 2016 to 24th last season. Houston also added cornerback Aaron Colvin in free agency and drafted safety Justin Reid with its first pick (third round) to help shore up the secondary.

Mike Wells, Indianapolis Colts reporter: Mathieu. What's already an impressive defense when everybody is healthy, including J.J. Watt and Jadeveon Clowney, improved with the addition of Mathieu. After spending his first five seasons in Arizona, Mathieu gives the Texans a playmaker on the back end with 11 career interceptions. He also gives them versatility, because he's capable of roving around to play multiple positions like cornerback or nickel linebacker if needed for a defense that fell to last in the NFL in points allowed last season after having the league's top unit in 2016.

Michael DiRocco, Jacksonville Jaguars reporter: Mathieu is the big-time playmaker the back end of Houston's defense needs. He can play cornerback, safety and nickelback. There aren't many players in the league who have the ability to not only do that, but to do it well. Mathieu has 11 interceptions and four forced fumbles in five seasons, but those numbers don't really reflect just how good of a playmaker he is. He's fast enough to cover on the outside as well as take someone in the slot or hold his own against tight ends. He has already shown he's going to be an issue for AFC South teams with what he did last season when he picked off Jacoby Brissett in overtime to set up Arizona's winning field goal against the Colts and intercepted Blake Bortles to seal the Cardinals' victory against the Jaguars.

Cameron Wolfe, Tennessee Titans reporter: Titans cornerback Malcolm Butler. He was the AFC South's biggest free agent, and he'll immediately become one of the Titans' best and most important players. Forget about the curious Super Bowl LII benching for a minute, because Butler is a No. 1 cornerback who helps elevate a talented Titans secondary. Butler has combined for 44 pass breakups (36) and interceptions (eight) since 2015, per Pro Football Focus, which is second among all cornerbacks. That type of production will be needed against AFC South receivers like DeAndre Hopkins and T.Y. Hilton. The Texans' addition of Mathieu is the runner-up here.